pnpm support

[TomRadford]

When running this CLI, the package manager selection doesnt have pnpm as an option.

---

Expected Behavior

🔗 Select framework: Astro
📦 Select package manager:
❯ yarn
npm
bun
pnpm

Current Behavior

🔗 Select framework: Astro
📦 Select package manager:
❯ yarn
npm
bun

Steps to Reproduce

1. pnpx @storyblok/create-demo@latest
2. Select any framework
3. pnpm isnt an option